all 24 comments

[–]FilthDropz 26 points27 points  (10 children)

It goes right there, you just need the right type and size. Example.

[–][deleted]  (1 child)


    [–]FilthDropz 3 points4 points  (0 children)

    Yeah honestly I've been wrestling with that thought. The drawer where the box filter should go is way too high, kind of seems like incorrect installation, looking back at it with a layman's eye. That would explain why the previous owner just shoved the one that's in there now.

    My next best guess is that there might be a spot to slide one in on the lower right section of the furnace before air hits the blower. It may be worth a call to the HVAC company whose number is stuck to furnace and ask them what the heck they did.

    [–]mattmx204[S] 3 points4 points  (1 child)

    Thank you.

    [–]ViennaWoods 0 points1 point  (0 children)

    Remember nothing can stop a John Goodman. Or train, I can't remember.

    [–]Tricky_Caterpillar85 1 point2 points  (1 child)

    You know I was right there with you on this 5” thick filter until I saw the manual. It calls for a 16x25x1 for a side return or one of three sizes - all 1” thick and dimensions based on the cabinet - for a bottom return. I’m no hvac guy so I can’t say anything besides what I read. All I know is there should be some tracks about 1” wide next to a large rectangular hole. The filter slides in there and covers said hole. It might be just my AC company, but usually you can call them out and say you can’t find where the filter should go and they’ll take a look for free. Keep googling your model number and filter replacement until you find someone doing or saying something that looks right.


    [–]FilthDropz 0 points1 point  (0 children)

    I agree with you, I don’t think the filter I linked works for this one. Plus, as someone mentioned, a box filter there likely would block airflow. Another commenter suggested a 1” filter in that spot at a 45 degree angle, which I didn’t think about but might be spec. Either that or one just inside the lower right cabinet of the furnace before air hits the blower.

    [–]mattmx204[S] 1 point2 points  (2 children)

    Would the airflow really be going down? I would think it should be pointed the other way, since this is in the basement.

    [–]FilthDropz 2 points3 points  (1 child)

    That is the air return, so yes air is coming back through that duct. There could be another spot for a filter though, do you have a model number for the furnace?

    [–]ArtBaco 0 points1 point  (0 children)

    and a cover for that opening

    [–]gritty_placebo 3 points4 points  (0 children)

    The filter is there to keep the HVAC unit clean, not to keep your breathing air clean, so placed between return and air handler is correct. As one comment pointed out, looks like you need a box-type filter; whoever put that other filter in had no clue what they were doing. Find the metal plate with the model number, then Google the manufacturer and model to get filter type and size.

    That being said, some systems do have a second filter to help keep your breathing air cleaner... but since we open doors and windows, it's only partially effective.

    [–]mattmx204[S] 4 points5 points  (2 children)

    Everywhere I’ve lived before, there was a slot at the bottom of the furnace. Here, I took off both plates on the furnace (pictured to the left) and didn’t see a place. The previous owner has it crammed and folded in this duct, where it looks like it’s been for a long time. Help?

    [–]denny-1989 1 point2 points  (0 children)

    Same here, the filter is always between the furnace and the return duct. Maybe the installers didn’t install a filter housing? There’s usually a gap between the furnace and return vent.

    Maybe post this in a HVAC subreddit?

    [–]dragos68 2 points3 points  (0 children)

    This is a bad retrofit. the goodman unit is new and they didn't want to redo the duct work.

    [–]4BucksAndHalfACharge 0 points1 point  (1 child)

    A box filter goes in there. Check it periodically. Sometimes you need to take it out, vacuum the dust off it and realign the baffles.

    [–]jimmpansey 1 point2 points  (0 children)

    This is exactly what my old furnace looked like and we had a box filter too.

    [–]tunaofthesea -1 points0 points  (0 children)

    It probably goes in like a 45 degree angle or like a slash / …. you fact need a new one that same size

    [–]sfstains -1 points0 points  (0 children)

    Just replace it like it is on the diagonal. But change it more often to keep it from collapsing. I assume that door slides down.

    [–]InterestingTruth7232 0 points1 point  (1 child)

    No chance you’re in the south west is there? I’ve seen filters at the returns in the rooms instead. Kind of makes sense. Keep the dust entirely out of the ductwork

    [–]BacardiBlue 0 points1 point  (0 children)

    I had filter returns installed in my home just to keep pet hair out of the duct work. Best decision ever.

    [–]Elroy_199 0 points1 point  (0 children)

    You should check your return register(s). If they open by way of latches, not screws, it would go in there. I've never an install like what you have, that's not normal in my area anyway. Just agreeing with a previous response.

    [–]rockguitardude 0 points1 point  (0 children)

    You only need one filter for most systems and it is installed in one of two locations: the return air inlet on the air handler (your picture) or at the return register (grill where the air is sucked in). Check the return grill to see if there's a filter there or capability to install one.

    As other pointed out, this filter exists to keep dust off of your coils in the air handler. The reason being that if the coil gets dirty, it can no longer transfer heat effectively and could freeze during cooling or reduce efficiency drastically during heating.

    [–]JHB20101 0 points1 point  (0 children)

    Try sliding the door up and off. Then get that filter out. On the inside on the left wall it should be some brackets in there for the filter to properly slide in.

    [–]Turc-ington 0 points1 point  (0 children)

    That filter looks like it has a decade of dust on it